<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>八进制和十六进制</title>
</head>

<body>
    <script>
        var y = 0377;
        var z = 0xFF
        document.write(y + "<br>");
        document.write(z + "<br>");
    </script>
</body>

</html>